Mixing enhancement of an active micromixer utilizing wall-mounted oscillating plates

• Published in: Journal of the Brazilian Society of Mechanical Sciences and Engineering 2024-07, Vol.46 (7), Article 396
• Main Authors: Abedini, E., Khosroshahi, A. R., Veladi, H., Hanifi, M.
• Format: Article
• Language: English
• Subjects: Actuator position; Amplitudes; Diffusion coefficient; Efficiency; Engineering; Flow simulation; Laminar flow; Mechanical Engineering; Moving walls; Technical Paper; Two dimensional flow; Vibration effects
• ISSN: 1678-5878; 1806-3691
• DOI: 10.1007/s40430-024-04988-7

In this study, the oscillation of walls in a Y-shaped active micromixer is considered to improve fluid mixing. Applying oscillation to the wall fortifies lateral convection and, consequently, improves mixing performance. Two-dimensional unsteady laminar flow simulations were conducted by COMSOL Multiphysics, and the effects of vibration amplitude, inlet fluid velocity, diffusion coefficient, actuator position, and two opposite oscillating parts’ settlement to one another and their phase difference on the mixing efficiency are evaluated. The results indicate the mixing performance improves by increasing the diffusion coefficient and oscillation amplitude of the moving walls as well as the proximity of the moving wall to the junction. The mixing efficiency increased from 25.4 to 90% at the micromixer outlet by increasing the oscillation amplitude from 10 to 97 μm. The efficiency decreased by 50% as the Re number increased from 0.0865 to 4.325. The micromixer performance, consisting of two symmetrical walls with simultaneous oscillations, improved by 70% at the distance of 2900 μ m from the junction compared with consecutive oscillation.